Who is it? That one enemy type who makes you want to grind your teeth in frustration?
For me, it'd beholders. I like playing CHARNAME as an Abjurer, and having all that fancy defensive magic rendered basically useless is annoying as crap. I'm basically forced into marching one guy armed with Balduran's Shield forward and winning instantly, or else rushing them and praying to the RNG that someone gets through the Save or Die's to mulch them.
For me, it'd beholders. I like playing CHARNAME as an Abjurer, and having all that fancy defensive magic rendered basically useless is annoying as crap. I'm basically forced into marching one guy armed with Balduran's Shield forward and winning instantly, or else rushing them and praying to the RNG that someone gets through the Save or Die's to mulch them.